blktrace: pass the right pointer to kfree()
Impact: fix kfree crash with non-standard act_mask string
If passing a string with leading white spaces to strstrip(),
the returned ptr != the original ptr.
This bug was introduced by me.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49DD694C.8020902@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index b32ff44..921ef5d 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1377,12 +1377,12 @@
{
int i;
int mask = 0;
- char *s, *token;
+ char *buf, *s, *token;
- s = kstrdup(str, GFP_KERNEL);
- if (s == NULL)
+ buf = kstrdup(str, GFP_KERNEL);
+ if (buf == NULL)
return -ENOMEM;
- s = strstrip(s);
+ s = strstrip(buf);
while (1) {
token = strsep(&s, ",");
@@ -1403,7 +1403,7 @@
break;
}
}
- kfree(s);
+ kfree(buf);
return mask;
}